Helicopter



FIG. 1 is a left side view of the helicopter;

FIG. 2 is a right side view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof.

Portions of the rotor blades in FIGS. 5 and 6 are shown broken away for convenience of illustration. 

The ornamental design for a helicopter, as shown and described. 